Due to the global increase in transmission capacities of data-packet-oriented communication networks, such as the Internet or local area networks (LANs), it has become increasingly popu1ar to use such data networks increasingly for voice communication. The problem in this case is that many widely used types of packet-oriented communication networks cannot guarantee a quality of service which is required for real-time voice transmissions.
To improve the real-time characteristics of voice transmissions via packet-oriented communication networks without guaranteed quality of service, various measures are known, for example from ITU-T Recommendation H.225.0 dated February 1998. Thus, for example, in section 8.5 of this document it is proposed, in conjunction with the retention of a predetermined quality of service, to lower the rate of transmission of the data packets in response to an increasing loss of data packets containing audio data. This measure is intended to reduce the transmission load and thus the packet loss rate. However, this control mechanism is severely restricted due to the real-time requirements of a voice transmission. In addition, the application of this measure is restricted to the transmitter end.